IgA nephropathy is the most common biopsy-proven pattern of glomerulonephritis in the world. Many factors, both clinical and histologic, have been suggested to impact on prognosis. We review the wide variations in how patients with immunoglobulin A nephropathy can present and the important differences derived from the clinical pathologic setting through the description of 4 cases. These include the clinical scenarios of modest proteinuria, acute kidney injury, and the nephrotic syndrome.